Genetic analysis of motor milestones attainment in early childhood

Abstract

The age of attainment for four motor developmental traits, such as turning over, sitting up without support, pulling up to a standing position and walking without support, was examined in 822 children, including 626 siblings from families with 2 to 6 children, 68 pairs of dizygotic twins and 30 pairs of monozygotic twins. Correlation analysis, carried out separately for each type of sibship, showed the highest pairwise correlations in monozygotic twins and the lowest correlation in non-twin siblings for all motor milestones. Variance component analysis was used to decompose the different independent components forming the variation of the studied trait, such as genetic effect, common twin environment, common sib environment and residual factors. The results revealed that the major proportion of the total variance after adjustment for gestation age for the attainment of each motor skill, except pulling up to standing position, is explained by the common twin environment (50.5 to 66.6%), whilst a moderate proportion is explained by additive genetic factors (22.2 to 33.5%). Gestational age was found to be an important predictor of appearance of all motor milestones, affecting delay of 4.5 to 8.6 days for the attainment of the motor abilities for each week of earlier gestation. The age of attainment of the standing position was affected only by shared sibs environment (33.3% of the total variance) and showed no influence of either genetic or common twin environment. Phenotypic between trait correlations were high and significant for all studied traits (range between 0.40 and 0.67, P < 0.01 in all instances). Genetic cross correlations, however, were not easily interpreted and did not show clear variance trends among the different groups of children.

Fetal Programming of Infant Neuromotor Development: The Generation R Study

“…The association between maternal length and maternal weight and the offspring's birth weight is in part explained by genetic influences (33,34). It is also known that maternal height and weight have a genetic influence on neuromotor functioning (35). Against this background, we considered maternal height and weight as potential confounders.…”

Delay in Motor Development of Twins in Africa: A Prospective Cohort Study

“…Breast-feeding has been shown to be associated with better development (Angelsen et al, 2001;Vestergaard et al, 1999), but all the infants in our study were breastfed for more than 6 months. Socioeconomic factors are likely to be important in global child development, although studies from developed countries reported a negligible influence of social class on the attainment of motor milestones (Capute et al, 1985b;Peter et al, 1999). However, in The Gambia there is no validated measure of socioeconomic status.…”

“…Motor development is likely to play a role in long-term neurodevelopmental status (Peter et al, 1999). This development can be impaired by a number of conditions.…”

Strategy and Practice of Support for Families with Multiple Births Children: Combination of Evidence-Based Public Health (EBPH) and Community-Based Participatory Research (CBPR) Approach

“…Many studies have shown that twins tend to lag behind singletons in terms of motor development (Chaudhari et al, 1997;Peter et al, 1999), although the causes of this delay are not explained simply by the earlier gestational age at birth or the lighter birthweight of twins compared to singletons. Relative to general population norms in Japan, twins tended to be delayed in reaching several motor development milestones (Ooki, 2006a).…”